Type 2 diabetes is an important and common health problem and disproportionately affects low income and minority populations. Acquiring diabetes self- management skills and applying them on a daily basis is challenging, especially for individuals with limited resources. Interventions utilizing community health workers (CHWs) improve knowledge and behavior among persons with diabetes, and in some studies have improved health outcomes. CHWs are a theoretically appealing way to reach vulnerable populations, however, additional work is needed to understand how and in what settings CHWs could most effectively impact diabetes care and reduce health disparities. Information regarding cost- effectiveness and return on investment is also needed. OBJECTIVES: We will test the hypotheses that CHWs providing in-home support for self- management of type 2 diabetes, resources for diabetes, and assistance in effective linkage and communication with medical providers will: (1) improve HbA1c (primary outcome) and secondary outcomes including blood pressure and lipid control, health care utilization, and health-related quality of life; (2) improve diabetes self-management, including self-efficacy, physical activity, nutrition, and medication adherence; and (3) be cost-effective and feasible. METHODS: We will implement a 5-year randomized controlled trial that will compare a CHW model consisting of in home diabetes self-management support, links to group support, and telephone support compared to usual care. CHWs will make up to 5 home visits over the course of a year to provide tailored support in the key components of self-management; referral to group activities including disease self-management classes; generate social support through relationships with their clients; and develop skills to navigate the health care system. At the end of the study period, usual care participants will receive a home visit by a CHW and diabetes self-management resources. The participants will be drawn from an ethnically and culturally diverse group of low-income patients age 30-70 who speak English or Spanish with type 2 diabetes and poorly controlled blood sugar and/or blood pressure who reside in King County, Washington. Participants will be recruited from the local Veterans Affairs (VA) hospital, the county hospital (Harborview) and a community health center (Sea Mar). Our primary outcome will be glycemic control as measured by a HbA1c. Secondary outcomes are blood pressure, lipids, health care utilization, health-related quality of life, self-efficacy and diabetes self- management behaviors. PUBLIC HEALTH RELEVANCE: This study will test the effectiveness of a community health worker intervention that includes home-based diabetes education and links to community resources in a diverse low-income population. We will develop a replicable and sustainable model that can be adopted by community-based organizations and local public health agencies. Given the increasing prevalence of individuals with type 2 diabetes, cost-effective mechanisms are needed to manage the burden of this chronic disease.